The present invention relates to bindery systems having a plurality of hoppers or feed stations at which signatures are fed to a conveyor, and is an improvement in such bindery system. For example, the invention is an improvement in a bindery system disclosed in U.S. Pat. application Ser. No. 141,331, filed May 7, 1971. In that system various magazines or books composed of various predetermined combinations of signatures are made in accordance with various subscriber information under the control of a computer. On the basis of information read from a magnetic tape, the computer instructs different ones of the signature feed stations to feed or not to feed to provide differently constituted magazines for different subscribers. At each feed station, the performance of the feeder in properly adding one signature is sensed by a sensor, and a malfunction code is generated when the sensor detects that the feeder does not operate properly. The malfunction code is shifted through a shift register to simulate the movement of the defective magazine through the remaining stations of the gatherer to a reject station and the magazine is rejected when it arrives at the reject station.